[Treatment strategies for chronic glenoid defects following anterior and posterior shoulder dislocation]

Abstract

Objective: Restoration of a stable, pain-free and functional shoulder in chronic glenoid defects following anterior or posterior shoulder dislocations.

Indications: Anterior glenoid defect: all recurrent or persistent shoulder instabilities in association with chronic glenoid lesions. Posterior glenoid defect: all recurrent or persistent postreposition shoulder instabilities with chronic osseous glenoid defects.

Contraindications: Brachial plexus injury. Poor glenoid bone stock.

Surgical technique: Anterior glenoid defect: exposition of the glenoid through a deltopectoral approach. Glenoid reconstruction by autologous iliac crest graft or coracoid transfer, in cases with progressive joint destruction in combination with shoulder arthroplasty. Posterior glenoid defect: exposition of the glenoid through a modified Brodsky approach from posterolateral. Exposure of the posterior capsule between infraspinatus and teres minor muscles, medial capsulotomy, glenoid reconstruction with auto- or allograft, normally by screw osteosynthesis. Treatment of the often accompanying anterior humeral head defect (reverse Hill-Sachs defect) by transposition of the lesser tubercle (modified from McLaughlin), defect coverage by auto- or allograft, or hemiarthroplasty through an anterior approach. In cases of persisting instability reconstruction of the glenoid defect with autologous graft and, if necessary, by shoulder arthroplasty.

Postoperative management: To preserve reconstructed anatomy, a Gilchrist sling is required in anterior reconstructions for 4-6 weeks. For postoperative treatment of posterior defects a thorax abduction splint is recommended for 6 weeks. Active-assisted reduced range of motion exercise is provided under physiotherapeutic guidance according to the individual pathology.

Results: Clinical results following open surgery of chronic glenoid lesions in shoulder instability differ from the treatment results in acute fractures because of the often accompanying large rotator cuff tears, bad bone quality and frequently large defect size. In the hands of experienced shoulder surgeons, however, favorable results can be achieved with modern implants, leading to decisive improvement in patients' quality of life.